title: Frequency- and time-domain analysis of P wave in patients with paroxysmal atrial fibrillation.
abstract: We investigated the usefulness of the time- and frequency-domain analysis of the P wave triggered signal-averaged ECG (P-SAECG) for detecting patients with paroxysmal atrial fibrillation (Paf). In previous studies, the usefulness of the time domain of the P-SAECG to detect patients with Paf was described but that of the frequency domain is unknown. We analyzed the P-SAECG in the time and frequency domain in 23 patients with Paf and 19 controls. The 32-unipolar chest lead ECGs and the standard bipolar limb lead ECGs were obtained. The time-domain analysis showed that the filtered P duration (fPd) was significantly longer (P < 0.01) in patients with Paf than controls: the predictive accuracy of Paf with fPd > 120 ms was 69%. The frequency domain analysis showed that the area ratio of power spectrum area of 0-20 Hz to 20-100 Hz (AR20) was significantly higher (P < 0.01) and the magnitude ratio at 30 Hz (%Mag.30) calculated by dividing the magnitude at 30 Hz by the maximal magnitude was significantly (P < 0.01) lower in patients with Paf than controls in the left lateral chest leads. The predictive accuracy of Paf with AR20 > or = 1.5 and that with %Mag.30 < 40% was 83% and 73%, respectively. Our results indicate that the frequency-domain analysis of P waves in lateral leads is useful as is the time-domain analysis to detect patients with Paf. The AR20 > or = 1.5 and %Mag.30 < 40% provides accurate predictability of Paf.
authors.affiliation: Third Department of Internal Medicine, Kurume University School of Medicine, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Hiraki
authors.forename: H
authors.initials: H
authors.lastname: Ikeda
authors.forename: M
authors.initials: M
authors.lastname: Ohga
authors.forename: T
authors.initials: T
authors.lastname: Hamada
authors.forename: I
authors.initials: I
authors.lastname: Kubara
authors.forename: T
authors.initials: T
authors.lastname: Yoshida
authors.forename: H
authors.initials: H
authors.lastname: Ajisaka
authors.forename: A
authors.initials: A
authors.lastname: Tanabe
authors.forename: M
authors.initials: M
authors.lastname: Kanahara
authors.forename: T
authors.initials: T
authors.lastname: Imaizumi
mesh_terms: D000328:Adult; D001281:Atrial Fibrillation / Q000175:diagnosis / Q000503:physiopathology*; D018880:Atrial Premature Complexes / Q000175:diagnosis; D004562:Electrocardiography / Q000379:methods*; D005260:Female; D005583:Fourier Analysis; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D012680:Sensitivity and Specificity; D012815:Signal Processing, Computer-Assisted